Start button does nothing fuel pump not priming

Joshmc628

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05 busa with 99 engine. Had issues with bogging out at low rpm so I changed spark plugs and took off fuel pump to clean it out. Put everything back together and the bike sounded amazing for a few seconds then cut off. Now the start button does nothing at all not even a clicking sound. Fuel pump also not priming.

I’ve tried: New battery, Bypass kickstand switch, bypass clutch switch, new fuse in every single slot, reseating relays, reseated connections on ecu, tried an entirely different killswitch.

With multimeter I’m getting no voltage at the fuel pump and no voltage at the starter. There is volts making it to fuse box. I can get the starter to spin by bridging the starter relay. It still doesn’t start because nothing is happening at the fuel pump (no volts there). Where do I go from here? I feel like I’ve exhausted all my knowledge so any help is appreciated
 
I know it is from my megasquirt,,,,,,,but it is plug and play
Busa 60 pin connector FOR MS3.png
 
Is tip over switch disconnects or in wrong place
Going to examine that next.
Do a search for ECU swaps and compatibility maybe .
ecu should work as I’ve taken my 05 flywheel and tps sensor and put on the 99 engine
Do a search for ECU swaps and compatibility maybe .
When you turn the key on do you get voltage to ECU large connector pin #17?
Nothing there, even took the pin out and tested it to ensure good connnection to multimeter.

7830DA93-D79D-45C3-B2DB-6CCA4BAD5B56.jpeg
 
Going to examine

ecu should work as I’ve taken

had to put in my 05 flywheel and tps sensor for it to work with this ecu. I’m hoping it’s not burnt out or something, gonna take a few we

Nothing there, even took the pin out and tested it to ensure good connnection to multimeter.

View attachment 1610470
If you are sure there is no voltage there, (some multi meter tips are too big) Probably not your ECU that wire needs to be 12v for the ECU to turn on
Start back chasing that wire till you find 12v
 
If you are sure there is no voltage there, (some multi meter tips are too big) Probably not your ECU that wire needs to be 12v for the ECU to turn on
Start back chasing that wire till you find 12v
Will do, thanks for putting me in the right direction
 
I would throw a test light between ground and that pin. then by just switching the key on you will see if it lights
Probably easier then voltmeter
No luck with a test light. Light turns on direct to battery but connecting it to pin 17 with ignition on does nothing. Looks like I may have to cut open this harness and trace this wire back?
 
I can look at a old beat harness I have to chase it But I am heading out for a couple hours
I was saying I would leave the test light between pin 17 and ground then you can just toggle the key and see, instead of having to fumble with a voltmeter

Unplug and re-plug all the connectors up under the headlight assembly
also wiggle all the wires to the RH control assembly
 
if not done yet, change the ´99 flywheel (generator´s rotor) to the ´05 and everything should work fine

the ´99 has only 8 outside "bumps" - the ´05 has 23 bumps

that´s the little fault in your system.

with the old ´99 rotor your ´05 system get not enough impulses - 23 it needs but it only get 8

you have to change the rotor but no other changing of cables or so is necesary.

i wonder a bit that the engine did start.
so control all fuses first - i have no clue but perhaps one of them melted
 
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if not done yet, change the ´99 flywheel (generator´s rotor) to the ´05 and everything should work fine

the ´99 has only 8 outside "bumps" - the ´05 has 23 bumps

that´s the little fault in your system.

with the old ´99 rotor your ´05 system get not enough impulses - 23 it needs but it only get 8

you have to change the rotor but no other changing of cables or so is necesary.

i wonder a bit that the engine did start.
so control all fuses first - i have no clue but perhaps one of them melted
Thanks but the flywheel has already been swapped as well as the camshaft sensor from the 05
 
If it ran, your swap was good. As pie-guy @SSGT_B said, check your tip over switch.
Alright tip over switch was still mounted nice and snug. Took it down and opened it up. Everything inside moving freely. Hooked it back up and now I can get starter to turn with the starter button(weird). Still no power to fuel pump and still no volts on pin 17 at ecu. Also getting flashing f1 light now and when I pulled the code it says c41.
 
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